Warm air is lighter than cool air

Q. In which of the following areas, will the climate remain almost the same throughout the year?

1. Desert area.
2. Near equator.
3. Coastal area.
4. Mountainous area.

Q.

The climate near the sea shore is moderate.

1. True
2. False

Q.

Fill in the blank:

When the velocity of gas molecules increases, their kinetic energy ______.

Q.

Take a metallic can half filled with water and put it over the flame so that the water inside starts boiling. Now put the lid on the can and remove it from the flame. What happens to the can when we pour cold water on it?

1. No effect is seen

2. Insufficient information

3. The can expands

4. The can contracts

Q.

As the temperature of the gas increases, the volume occupied by the gas ___.

1. increases
2. decreases
3. remains constant
4. first decreases and then increases

Q. The volume of the air _______, when we heat the air.

1. increases
2. becomes zero
3. decreases
4. doesn't change

Q.

Warm air is ______ than cold air.

1. heavier
2. either heavier or lighter
3. lighter
4. denser

Q.

If we take same amount of hot and cold air, in a given fixed volume of a container, then which of the following statements is correct?

1. Hot air exerts more pressure on the walls of the container.

2. Cold air exerts more pressure on the walls of the container.

3. Both hot and cold air exert same pressure on the walls of the container.

4. Pressure of hot and cold air cannot be compared.

Q.

What happens to air when it is heated?

1. Movement ceases

2. Contracts

3. Expands

4. Moves down

Q.

Beakers A and B have the same amount of air initially. The beakers are dipped in water at different temperatures. Which of the following statements is correct with respect to the given figure?

1. Water in both the beakers is at the same temperature.
2. Water in beaker A is hotter than that in B.
3. Water in beaker B is hotter than that in A.
4. Temperature of water in beaker A and B cannot be predicted.

Q.

Warm air is less denser than cold air.

1. False

2. True

Q. Warm air is ______ than cold air.

1. Lighter
2. Denser
3. Heavier
4. None of the given options

Q. We have learned about kinetic energy and its relation to the heat. State true or false:

The kinetic energy of the air particle increases if we increase its speed.

1. True
2. False

Q.

Hot air is less dense than cold air.

1. True

2. False

Q.

With the increase in kinetic energy of the air molecules, the tendency to occupy space by those air molecules will _____________.

1. decrease

2. increase

3. remain the same

4. become zero